Hello!

For a bit of context, my aim is to host Ubuntu on a Rocket RISCV powered SoC using the Litex toolchain https://github.com/enjoy-digital/litex. I am using OpenSBI as my bootloader https://github.com/riscv-software-src/opensbi. The kernel which I am using is Litex's fork of the kernel https://github.com/litex-hub/linux on the litex-rebase branch. This fork has driver support for the custom peripherals and components which the Litex SoCs uses.

I am using an Ubuntu cloud image https://cloud-images.ubuntu.com/jamm...mg-riscv64.img and have modified fstab (loading dependencies into the FPGA using sdcard, one partition containing bootloader, kernel image, initrd, another containing root filesystem).

I have built a kernel image and an initrd which I side-load into the SoCs memory from SD Card, which the bootloader invokes. Please read https://www.contrib.andrew.cmu.edu/~...ng_fedora.html to see the guide which I used for configuring Ubuntu (Yes I know it is for Fedora but both use systemd as init process, maybe this is nativity)

The kernel panic which I encounter is a bit beyond me, though I did research some of the key errors I would like to ask for some support.

Please find attached bellow the console log, SoC device tree file, as well as kernel configuration file which I am using
https://github.com/enjoy-digital/lit...log_ubuntu.txt

https://github.com/enjoy-digital/lit...dts_ubuntu.txt

https://github.com/enjoy-digital/lit...552/defcon.txt


PS: I’m new to LQ so please be patient!

—Thanks

Hello, beanthenewbieengineer and wwelcome to LQ.

Let me politely suggest that you change your handle, because you won't be a newbie forever (I hope) and there are seriously qualified guys here so 'engineer' sounds like boasting.

I don't like the sound of what you're doing and am not surprised it's failing. You can't fart about with toolchains. The toolchain consists of Glibc, kernel headers & gcc generally. Every program uses /lib/ld-linux.so (which these days points to /lib/ld-<version>.so) for basic I/O. If you get your /lib/ld-linux.so from glibc-2.33, stuff compiled against glibc-2.32 & earlier won't run. When you say I take it you're trying to RUN ubuntu?

If so, you've got a toolchain - the Ubuntu one. So you should compile your drivers with the Ubuntu toolchain, providing they put the source code up there for you to use.

If Litex don't put the driver source online, do they have a decent RiscV OS? If they don't have either, stop and rethink. I've done the FPGA think myself, and that's a competitive space. If you look in the arch/ directory, you'll see a number of architectures in various states. Most of them are cpus specific to a FPGA manufacturer, provided to lock you in to their FPGAs. They will have plenty of in-house support for them, if not the RiscV. Also, watch the wafer fab size. As things speed up, they need to be getting the fab size down. Xilinx are the handiest for linux, but last I checked, their speed was slow. That was about 10 years back, but I settled on Quartus then.

This is now. Do the homework if Litex don't give you what you want. Another manufacturer may be better, unless, of course, you're locked into Litex.

I'm not interested in your project. Take a photo of the screen with you mobile to catch the kernel panic. It's the bit before the stack trace that we need to see.